I completed the Cascade 1200 on a Catrike Speed last year, and I am heading to France in a week to ride PBP on the same trike. I am about as fast on the trike as I was on the Specialized Sequoia that I used for 4 seasons of rando rides. The significantly more aero position makes headwind a lot less noticeable, and makes downhills a lot faster, and more fun. The recumbent position improves the overall seat comfort, which for me is critical in rides longer than a 600k, and there is no pressure on the hands from leaning on the handlebar (numbness was an issue on 1000k and 1200k rides on my previous bike). The inherent stability of riding on three wheels is safer (or at least feels safer) when I am having a hard time staying awake on the last 1/3 of a 1200 randonnee. As an added bonus, I can take roadside naps without even getting out of the vehicle. Climbing is slow, but mostly because I am carrying 10 kg of excess weight on my body. I was slow on my old bike as well. The 20" rear wheel, and the relatively low gears, let me spin uphill to climb easily on steep hills that other riders walk. Visibility is not an issue, but then I have copious amounts of reflective tape on the frame, the rims, the fender, and I use a high-viz flag that is also very reflective, in addition to a bright tail light. I have a feeling that drivers notice you more on a trike because you are very different, and they are not quite sure of what you are.
The big drawback for me is that between the fact that your head is a lot lower than on an upright bike, and the speed difference on uphill and downhill sections, makes it hard to ride in a group with more traditional bikes, and have a conversation with other riders. But it is not impossible: I was on a night 200k brevet with 4 other riders two weeks ago, and we stayed together and had great conversations and a great time. The social aspect of rando riding is very important for me.